A pregnant woman's antenatal serology shows: HBsAg positive, HBeAg positive, anti-HBc IgM negative, anti-HBc IgG positive, HBV DNA 5 × 10^7 IU/mL. She is at week 28 of gestation. Which management strategy best reduces the risk of perinatal hepatitis B transmission?
- A Tenofovir disoproxil fumarate (TDF) from week 28–32, plus neonatal HBsAg vaccine + HBIG at birth ✓
- B Neonatal vaccine and HBIG at birth alone, without maternal antiviral
- C Interferon-alpha therapy starting at week 28
- D Lamivudine monotherapy for the mother with no neonatal immunoprophylaxis
Correct answer: A. Tenofovir disoproxil fumarate (TDF) from week 28–32, plus neonatal HBsAg vaccine + HBIG at birth
Explanation
In highly viraemic mothers (HBV DNA >200,000 IU/mL or HBeAg positive), neonatal immunoprophylaxis alone (vaccine + HBIG) has a 5–10% failure rate; adding maternal TDF from weeks 28–32 reduces HBV DNA to low levels by delivery, reducing neonatal exposure. WHO 2020 guidelines and NACO recommend TDF as the preferred antiviral in pregnancy. Interferon is contraindicated in pregnancy. Lamivudine monotherapy has higher resistance rates and lower potency than TDF. Neonatal vaccine + HBIG within 12 hours of birth is essential alongside maternal treatment.
Reference: Ananthanarayan & Paniker's Textbook of Microbiology, 11th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.